Brisbane Roar goalkeeper Michael Theo has urged fans to "stay loyal", declaring the champions have not lost their winning culture despite a fifth defeat in eight A-League games at the weekend.

Things could get even tougher at home against Newcastle on Saturday if three key players, defenders Matt Smith and Ivan Franjic and young attacking speedster Ben Halloran, travel to Hong Kong with Holger Osieck's Socceroos.

A 2-1 loss to Central Coast at Bluetongue Stadium, where they had never previously lost in 13 visits, has the Roar in second last place and coach Rado Vidosic under fire to make some changes.

Brisbane fans have been used to their team winning and a further loss could trigger a supporter backlash in coming weeks if they can't turn things around.

"I hope they remain loyal. The past few years as a team and as players we've probably been spoilt," Theo said.

"We're not used to losing and it's very strange for us.

"We hope they (supporters) remain loyal and patient. We know they're frustrated but I tell you what, there's another 25 players and coaching staff who are just as frustrated as they are.

Theo said the players were "gutted" by the weekend but would not dwell on the result.

He said despite some negative press the club still had a winning mentality built on the success it enjoyed from back-to-back titles.

"You don't become bad players overnight," he said.

"Things aren't going our way and everything gets magnified.

"We know when we're up to our standards and when we play that the result usually goes in our favour."

Vidosic should know by Thursday how many of his trio Osieck need for Australia.

If Smith and Franjic go to Hong Kong, Vidosic will have to gamble on an untried defence in front of Theo with 19-year-old Japanese-born Yuji Takahashi, inexperienced central defender James Donachie both possibilities along with Matt Jurman.

"We have conceded some soft goals we're not happy about and quite often the first goal in the opening minutes which is something we have to turn around quickly," Theo said.

"If we lose two or three players this weekend (to Socceroo duty) it will be a great opportunity for one of the younger boys to step up and grab his chance and put in a good performance."